Modular mid-scale liquefied natural gas production system and method

ABSTRACT

The present disclosure provides a system and method of efficiently designing a compact and modularized midscale liquefied natural gas production train. The train includes Natural Gas Pretreatment and Natural Gas Liquefaction sections designed in a unique way that reduces footprint, capital and operating cost, and overall project schedule. The train is configured into a framed compact multi-level structure with air coolers on the top level and process equipment underneath, which results in significant reduction in footprint compared to conventional stick-built design and significant reduction in footprint compared to conventional modularized design.

CROSS REFERENCE TO RELATED APPLICATIONS

Not applicable.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO APPENDIX

Not applicable.

BACKGROUND OF THE INVENTION Field of the Invention

The disclosure generally relates to hydrocarbon production facilities.More specifically, the disclosure relates to modular and compactproduction facilities of hydrocarbons such as liquefied natural gas.

Description of the Related Art

A large portion of natural gas traded internationally is in the form ofLiquefied Natural Gas (“LNG”). Liquefaction plants/terminals constitutea key link in natural gas value chain, producing LNG from natural gasvia a cryogenic process, store the product in large storage tanks, andthen load the LNG into LNG carriers bound for export destinations.

Liquefaction plants are traditionally arranged in trains. A train is acollection of process systems necessary to perform complete function ofprocessing gaseous feed gas and converting it into liquid LNG product. Aliquefaction train can vary in size from small-scale to mid-scale tolarge-scale with distinct selections of technologies and equipment. Thecapacity of a mid-scale train is generally in the range of 1 to 3.5million tons per annum (“MTPA”) LNG production. An onshore base loadliquefaction plant often consists of multiple identical trains, sometimeconstructed at different times. The trains are served by other commonfacilities located outside battery limits (OSBL), including utilities,LNG storage, LNG loading, marine systems, and so forth.

In the past, onshore LNG plants are mostly “stick built”, which is builton site with individual components as a traditional method ofconstruction. The construction process takes thousands of onsiteconstruction workers at a time and could last years to finish. Stickbuilt LNG plants usually occupy massive real estate.

During recent years, modular construction has been increasingly appliedin LNG project execution, which in many cases shortens project scheduleand reduces risks, at the same time saving cost. However, the extent ofmodularization and its specific implementation varies a great deal fromproject to project. The following observations are made in literature ofmodular LNG train design.

First, modularization remains a construction method rather than a designphilosophy. Consequently, a train has the same or similar configurationand layout as a conventional stick built one, only to be sliced up intosmaller sections when it comes to construction execution. Oneconsequence is a very large train footprint due to most processequipment being located on the base level, even though the equipment mayhave been included in different modules.

Second, only parts of the train are modularized, leaving the remainingsections still to be stick built. This is prevalent in most of thecurrent “modular” trains. Non-modular sections of the train ofteninvolve components that are challenging to be modularized, for exampletall and heavy columns, liquefier, large rotating equipment, pipe rack,electrical/instrumental equipment, and others. The U.S. Pat. No.10,539,361, for instance, has much equipment located in unframedsections or even outside modules. As a result, the train footprintremains significant and a substantial amount of field work is stillrequired.

Third, a large number of modules is often required to construct acomplete LNG train, which increases exponentially with train size. Thenumber and size of modules rely on many practical constraints in modulefabrication, marine shipping, road transportation, and other factors. Atrain, especially a large-scale one, is sometimes divided into dozens ofmodules, which leads to a large number of interfaces/golden welds to beconnected in the field. It also adds complexity and uncertainties toconstruction execution, as all these modules could be built and shippedfrom different yards around the globe, that need to be managed andcoordinated. From this perspective, less number of modules are desirablefor which mid-scale trains offer better prospects.

Given these shortcomings in prior art, alternate and better designs aremuch needed to realize full benefits from LNG train modularization.

BRIEF SUMMARY OF THE INVENTION

The present disclosure provides a system and method of efficientlydesigning a compact and modularized midscale liquefied natural gas(“LNG”) production train. The train includes Natural Gas Pretreatmentand Natural Gas Liquefaction sections designed in a unique way thatreduces footprint, capital and operating cost, and overall projectschedule. The modularized train can contain substantially completeprocess systems required for natural gas pretreatment (including inletgas reception, mercury removal, acid gas removal, dehydration, heaviesremoval) and liquefaction (including pre-cooling, condensing,subcooling, and refrigerant circuits). Necessary hardware includingmechanical and electrical equipment, piping and instrumentation are allincluded. The train is configured into a framed compact multi-levelstructure with air coolers on the top level and process equipmentunderneath, which results in significant reduction in footprint comparedto conventional stick-built design and significant reduction infootprint compared to conventional modularized design. In at least oneillustrative comparison, the inventive modularized midscale liquefiednatural gas production train results in about 30% reduction in footprintcompared to conventional stick-built design and about 10% reduction infootprint compared to conventional modularized design.

The inefficiencies of prior art are removed in the new method describedin this invention. The efficiency of compactness is further improved byarranging process equipment/ systems in a strategic and unique way in atleast one or more of the following:

-   -   By combining vacant spaces required for multiple purpose, such        as maintenance access, safety distance, and process technology        reasons;    -   The LNG liquefier and rundown line and associated piping are        located in a way to minimize cryogenic liquid lines and        concentrating the lines and equipment with cryogenic service in        small area at the end of module;    -   The air coolers with high duty are arranged on one side for        minimizing air recirculation;    -   The compressor drivers are located at the ends of module for        ease of installation and maintenance;    -   The large compressors requiring large motor drivers and variable        frequency drives are located on the extremities of the modules;        this allows the high tension cables to be outside the modules        and not in close proximity of other “inside battery limits”        (“ISBL”) equipment, which enhances the safety of the plant;    -   Due to short length of LNG run down line, the vacuum insulated        pipes are used which avoids LNG troughs for spill containment        and this achieves superior safety and cost effective        pre-fabricated design;    -   The air coolers located close to gas turbines are provided with        high air flow fans to increase the air flow from the air coolers        to prevent hot air recirculation to the gas turbine air intake;        and    -   The local electrical rooms and/or substations on the module        located at outside edges of the module away from LNG rundown        lines and cryogenic area.

This strategic placement of the equipment also leads to low hydrocarboninventory of LNG and other cryogenic fluids which leads further tocompactness without compromising the process safety. Furthermore, thestrategic design of module(s) provides flexibility to add options withno impact to overall module design and equipment layout.

The disclosure provides a modularized liquefied natural gas productiontrain, comprising: a framed multi-level structure comprising natural gasliquefaction process systems required for natural gas pretreatment,liquefaction, and refrigerant compression and related hardware includingmechanical and electrical equipment, piping and instrumentation; whereinair coolers are installed on a top level of the structure with otherprocess equipment located on multiple levels underneath the air coolers;wherein the structure has a central pipe rack the runs a longitudinallength of the structure with equipment located on both sides of thecentral pipe rack; and wherein one more refrigerant compressors andrelated power drivers are located at an end of the structure.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawing(s) will be provided by the Office upon request and paymentof the necessary fee.

FIG. 1 is a representation of a footprint comparison between a stickbuilt facility, conventional modularized (semi-modular) built facility,and the inventive modular built facility having similar function andproduction.

FIG. 2A is a schematic side view of an inventive embodiment of themodularized fully framed multi-level structure.

FIG. 2B is a schematic isometric view of the modularized fully framedmulti-level structure of FIG. 2A.

FIG. 3 is a schematic top view of an illustrative layout of variousequipment of each side of the central corridor that distributes weightand shape symmetry of a module.

FIG. 4A is a schematic enlarged end view of the modularized fully framedmulti-level structure of FIGS. 2A-2B, illustrating a central corridorand central pipe rack.

FIG. 4B is a schematic enlarged side view of the modularized fullyframed multi-level structure of FIGS. 2A-2B, illustrating a centralcorridor and central pipe rack.

FIG. 5 is a schematic diagram of divisional flexibility of modules forthe modularized fully framed multi-level structure of FIGS. 2A-2B.

FIG. 6A is schematic top view of an illustrative location forrefrigerant compressors drivers, such as motors.

FIG. 6B is schematic top view of an illustrative location forrefrigerant compressors drivers, such as gas turbines.

FIG. 7 is schematic top view of an illustrative routing for cryogenicservice lines, such as a rundown line.

FIG. 8 is schematic top view of an illustrative routing for cryogenicequipment and piping, including a rundown line routing.

FIG. 9 is schematic top view of an illustrative location for pumps.

FIG. 10 is schematic top view of an illustrative location for astationary hydraulic lift and laydown area.

FIG. 11 is schematic top view of an illustrative location for built-indrain drums.

DETAILED DESCRIPTION

The Figures described above and the written description of specificstructures and functions below are not presented to limit the scope ofwhat Applicant has invented or the scope of the appended claims. Rather,the Figures and written description are provided to teach any personskilled in the art how to make and use the inventions for which patentprotection is sought. Those skilled in the art will appreciate that notall features of a commercial embodiment of the inventions are describedor shown for the sake of clarity and understanding. Persons of skill inthis art will also appreciate that the development of an actualcommercial embodiment incorporating aspects of the present disclosurewill require numerous implementation-specific decisions to achieve thedeveloper's ultimate goal for the commercial embodiment. Suchimplementation-specific decisions may include, and likely are notlimited to, compliance with system-related, business-related,government-related, and other constraints, which may vary by specificimplementation, location, or with time. While a developer's effortsmight be complex and time-consuming in an absolute sense, such effortswould be, nevertheless, a routine undertaking for those of ordinaryskill in this art having benefit of this disclosure. It must beunderstood that the inventions disclosed and taught herein aresusceptible to numerous and various modifications and alternative forms.The use of a singular term, such as, but not limited to, “a,” is notintended as limiting of the number of items. Further, the variousmethods and embodiments of the system can be included in combinationwith each other to produce variations of the disclosed methods andembodiments. Discussion of singular elements can include plural elementsand vice-versa. References to at least one item may include one or moreitems. Also, various aspects of the embodiments could be used inconjunction with each other to accomplish the understood goals of thedisclosure. Unless the context requires otherwise, the term “comprise”or variations such as “comprises” or “comprising,” should be understoodto imply the inclusion of at least the stated element or step or groupof elements or steps or equivalents thereof, and not the exclusion of agreater numerical quantity or any other element or step or group ofelements or steps or equivalents thereof. The terms “top”, “up”,“upward”, “bottom”, “down”, “downwardly”, and like directional terms areused to indicate the direction relative to the figures and theirillustrated orientation and are not absolute relative to a fixed datumsuch as the earth in commercial use. The term “inner,” “inward,”“internal” or like terms refers to a direction facing toward a centerportion of an assembly, component or system, such as longitudinalcenterline of the assembly, component or system, and the term “outer,”“outward,” “external” or like terms refers to a direction facing awayfrom the center portion of an assembly, component, or system. The term“coupled,” “coupling,” “coupler,” and like terms are used broadly hereinand may include any method or device for securing, binding, bonding,fastening, attaching, joining, inserting therein, forming thereon ortherein, communicating, or otherwise associating, for example,mechanically, magnetically, electrically, chemically, operably, directlyor indirectly with intermediate elements, one or more pieces of memberstogether and may further include without limitation integrally formingone functional member with another in a unitary fashion. The couplingmay occur in any direction, including rotationally. The order of stepscan occur in a variety of sequences unless otherwise specificallylimited. The various steps described herein can be combined with othersteps, interlineated with the stated steps, and/or split into multiplesteps. Similarly, elements have been described functionally and can beembodied as separate components or can be combined into componentshaving multiple functions. Some elements are nominated by a device namefor simplicity and would be understood to include a system of relatedcomponents that are known to those with ordinary skill in the art andmay not be specifically described. Various examples are provided in thedescription and figures that perform various functions and arenon-limiting in shape, size, description, but serve as illustrativestructures that can be varied as would be known to one with ordinaryskill in the art given the teachings contained herein. As such, the useof the term “exemplary” is the adjective form of the noun “example” andlikewise refers to an illustrative structure, and not necessarily apreferred embodiment. Element numbers with suffix letters, such as “A”,“B”, and so forth, are to designate different elements within a group oflike elements having a similar structure or function, and correspondingelement numbers without the suffix letters are to generally refer to oneor more of the like elements. Any element numbers in the claims thatcorrespond to elements disclosed in the application are illustrative andnot exclusive, as several embodiments may be disclosed that use variouselement numbers for like elements.

The present disclosure provides a system and method of efficientlydesigning a compact and modularized midscale liquefied natural gasproduction train. The train includes Natural Gas Pretreatment andNatural Gas Liquefaction sections designed in a unique way that reducesfootprint, capital and operating cost, and overall project schedule. Thetrain is configured into a framed compact multi-level structure with aircoolers on the top level and process equipment underneath, which resultsin significant reduction in footprint compared to conventionalstick-built design and significant reduction in footprint compared toconventional modularized design.

FIG. 1 is a representation of a footprint comparison between a stickbuilt facility, conventional modularized (semi-modular) built facility,and the inventive modular built facility having similar function andproduction. The present invention train design 2 (shown in FIGS. 2A and2B) is configured into a framed and compact multi-level structure withair coolers on the top level and process equipment underneath, whichresults in about 30% reduction in footprint compared to conventionalstick-built design 4 and about 10% reduction in footprint compared toconventional modularized design 6. The compactness is important for atleast two reasons. For instance, a train with 2.0 MTPA nominal capacityusing the present invention measures about 800 feet (245 meters) long,128 feet (40 meters) wide. Secondly, modules are often shipped tolocation and moved from the ship with motorized transports. Thefootprint is limited by the ship. Compaction allows more equipment andpotentially more production from the same footprint. The inventionaccomplishes the increased compaction over even current modularizationdesigns.

FIG. 2A is a schematic side view of an inventive embodiment of themodularized fully framed multi-level structure. FIG. 2B is a schematicisometric view of the modularized fully framed multi-level structure ofFIG. 2A. FIG. 3 is a schematic top view of an illustrative layout ofvarious equipment of each side of the central corridor that distributesweight and shape symmetry of a module. FIG. 4A is a schematic enlargedend view of the modularized fully framed multi-level structure of FIGS.2A-2B, illustrating a central corridor and central pipe rack. FIG. 4B isa schematic enlarged side view of the modularized fully framedmulti-level structure of FIGS. 2A-2B, illustrating a central corridorand central pipe rack.

Contrasting to prior art, the present invention can configure an entireLNG train 10 into a fully framed multi-level structure. Such a structurenot only provides space to contain all components within the train, butalso is supported adequately for marine and road transportation eitheras one or multiple modules. The first level 12 (also referred to as abottom deck herein) is a structural base and is elevated from the groundor other supporting surface to allow roll-on roll-off transportation onship and shore with self-propelled module transporters (“SPMT”) 14. Aircoolers 16 are installed on a top level 18 of the structure and otherprocess equipment are located in levels underneath the top level withthe air coolers. Tubes coupled with the air coolers can include at leastportions of high flux tubes. The air coolers can be installed so thatair coolers that collectively form a majority heat load of the train andair flow are installed on one portion of the top level to reduce hot airrecirculation and reduce a size of at least a portion of the aircoolers. Further, an air cooler located in proximity to a gas turbinecan include a high air flow fan to reduce hot air recirculation to anintake of the gas turbine.

Compression equipment, such as a booster compressor 76, can be locatedon one side of the central corridor 26 in a pre-treatment section (suchas pretreatment module 66) and process towers 68 can be located on anopposite side of the pipe rack 24 of the central corridor 26. At leastsome of the compression equipment can be located at an edge, such as acorner, of the train for easy replacement and maintenance access. Also,large compressors requiring large motor drivers and variable frequencydrives are generally located on the edges of the modules. This locationallows high tension cables to be outside the train and not in closeproximity of other ISBL equipment, which enhances the safety of theplant.

Multiple levels 20 allow vertical offset among equipment and enablesmore compact layout. As a result, the train footprint is significantlysmaller compared with other designs with the same capacity as describedin FIG. 1 above.

The train 10 structure has a built-in central pipe rack 24, shownparticularly in FIG. 4A, along the train length in the longitudinaldirection. Equipment are placed on both sides of the pipe rack. Thiscentral pipe rack 24 provides easy and organized connectivity for pipingand cables. A central corridor 26 is consequently formed within thetrain structure that combines the vacant space required for safetydistance (such as reduced overpressure in case of explosion) andmaintenance access, and hence achieved superior compactness overconventional designs.

A pre-cooling heat exchanger 82 can be located on one side of thecentral corridor 26 in a liquefaction section (such as liquefactionmodule 54) and a liquefier 50 can be located on an opposite side of thecentral corridor. In this way, superior weight distribution and shapesymmetry of the module is achieved.

Local electrical rooms and/or substations 84 can be located at outsideedges 86 of the train and distal from liquefied natural gas rundownlines and a cryogenic area, described above, to have clean air intakeaccess. Also, instrument junction boxes 88 can be located along thecentral corridor 26, distal from liquefied natural gas rundown lines anda cryogenic area.

FIG. 5 is a schematic diagram of divisional flexibility of modules forthe modularized fully framed multi-level structure of FIGS. 2A-2B.Consistently designed and framed and supported throughout, the elongatedtrain structure can be further divided into multiple modules, whenjustified by specific needs of a project. Great flexibility exists individing the train into multiple modules along the latitudinaldirection, without altering overall train structure design and equipmentlayout. A single module is possible for the entire train of smallcapacity. A mid-scale train would generally have three modules. Whenarriving at the site, individual modules are installed back-to-backalong the train longitudinal direction with aligned central pipe rackand leveled decks. As examples, various different ways of moduledivision include but are not limited to:

-   -   In one embodiment, the train structure 30 can be one single        module;    -   In one embodiment, the train structure 32 can be divided into a        process module and a refrigerant compressor(s) module;    -   In one embodiment, the train structure 34 can be divided into a        pretreatment module, a liquefaction module, and a refrigerant        compressor(s) module.    -   In one embodiment, the train structure 36 can be divided into a        pretreatment module and a liquefaction/refrigerant compressor(s)        module.

FIG. 6A is schematic top view of an illustrative location forrefrigerant compressors drivers, such as motors. FIG. 6B is schematictop view of an illustrative location for refrigerant compressorsdrivers, such as gas turbines. FIGS. 6A and 6B illustrates twoalternatives with electric gas motors and turbines, respectively. LNGliquefaction is achieved by exchanging heat with circulatingrefrigerant, hence the duty required to cool and/or condense refrigerantis very significant. In an air-cooled liquefaction train, the heat isrejected via a very large number of air coolers into the atmosphere as aheat sink. To avoid taking additional plot space, air coolers in priorart are often placed on top of the pipe rack. Such solutions however areconstrained by the available width of the pipe rack. It is not uncommonfor a liquefaction train to extend extra distance in length (that is,longitudinal) direction just to accommodate air coolers. There are alsodesigns to build structures dedicated for air coolers or useself-standing air coolers, which in either case would require largeadditional plot.

With a fully framed train 10 structure of the present invention, a largeopen top level 18 is formed and is made available for air cooler 16installation. There is a lot more space in width (i.e. latitudinal)direction compared to only the pipe rack as in prior art. With thegeometry of air coolers carefully selected, at least two air coolerbanks 38A and 38B are arranged side-by-side fully occupying the toplevel width. The air coolers can be installed on the top levelindependent of any cantilever extensions extending laterally from thetrain. As a result, no additional footprint structure is required forair coolers.

In the present invention, refrigerant compressor(s) 40 and refrigerantcompressor power driver(s) 42 are strategically located at an end 44 ofthe elongated train 10 structure, such as the end of a compressionmodule 46, allowing easy access for maintenance. In addition, thecompressor(s) and driver(s) can be aligned such that their shafts are inparallel with the longitudinal length of the train, including parallelwith the length of the pipe rack 24, described above. With being locatedat the end 44 of the train 10, the power driver 42 is interchangeablebetween gas turbine driver and electric motor driver. Such a locationalso provides flexibility to accommodate compressor design variability(such as barrel vs. horizontal split casing, single vs. multiple bodies,and so forth), causing little if any impact on overall train structuredesign and equipment layout.

FIG. 7 is schematic top view of an illustrative routing for cryogenicservice lines, such as a rundown line. When a gas turbine is used, itsair intake 48 is oriented away from process equipment located inside thetrain structure. This improves safety by reducing possible entrainedflammable hydrocarbons in the air entering the gas turbine. It alsoreduces potential hot air recirculation from air coolers.

One or two Liquefiers for LNG precooling, condensing, and subcooling maybe required depending on liquefaction processes. The present inventiondiffers in that the liquefier(s) 50 can be installed at a reservedlocation within the train 10 and supported by the train structure. Thisenclosed liquefier design shortens the inter-connecting piping betweenthe liquefier 50 and connecting equipment, and hence reduces containedhydrocarbon liquid inventory such as LNG or refrigerant. It allows thetrain 10 structure to provide support for the liquefier and avoid adedicated support structure often required to support this tallexchanger and its associated piping and valves. In the case ofmulti-train layout, the spacing between the two adjacent trains inparallel can be reduced without the liquefier(s) sticking out.

The liquefier 50 located at an end 52 of a liquefaction section 54, theLNG rundown line 56 can be routed outside of the structure boundary fromthe same end and away from the train resulting in minimum length of LNGrundown line 56 within the train 10 leading to minimum inventory of LNGwithin the train and thus enhanced safety. Due to short length of LNGrun down line 56, vacuum insulated pipes 58 can be used. By using vacuuminsulated pipes 58, LNG troughs are not needed for spill containment.The design helps achieve superior safety and cost effectivepre-fabricated design.

FIG. 8 is schematic top view of an illustrative routing for cryogenicequipment and piping, including a rundown line routing. The LNGliquefier 50 and rundown line 56, shown in FIG. 7 , and associatedpiping are located in a way to minimize cryogenic liquid lines andconcentrating the lines and equipment with cryogenic service in a smallcryogenic area 60 at the end 52 of liquefaction module 54 in thisembodiment. Thus, the design achieves high compactness and enhancedsafety.

FIG. 9 is schematic top view of an illustrative location for pumps.Pumps 62 can be located on the first level 12 along sides 64 of thecentral corridor under the pipe rack for easy maintenance access. Also,all the pumps in the liquefaction module 54 and pre-treatment module 66(shown in FIG. 8 ) can be localized in a small area which allows forcollection of potentially contaminated rainfall water from directlyunderneath the pumps and thus permitting a significant capital costsavings for a reduced water treatment system capacity.

FIG. 10 is schematic top view of an illustrative location for astationary hydraulic lift and laydown area. The central corridor 26 isdesigned to safely accommodate any removed item from within the trainthat requires maintenance and transfer to a lift system 70 on a firstlevel 12 that can be installed at an end 72 of a module. The lift system70 can be hydraulic. Upper levels can have drop zone openings 74 to thefirst level 12 within the central corridor 26. The drop zone openings 74allow for superior ergonomics, a further safety escape system, and awell-ventilated area for maintenance.

FIG. 11 is schematic top view of an illustrative location for a built-indrain system. Oily water and chemical drain systems 78 are pre-installedwithin the module frames beneath the bottom deck and distal from the LNGrundown lines and cryogenic area described above.

While the modularized liquefied natural gas production train has beendescribed above with some specificity, the train is not limited to sucha configuration. For example, the number of levels and modules, heightof the bottom deck above grade, location of various sections in modules,and other features can vary. In some cases when module transportationbecomes a constraint, the train could be stick built with the samelayout concept to achieve compactness and cost reduction. Other andfurther embodiments utilizing one or more aspects of the inventionsdescribed above can be devised without departing from the disclosedinvention as defined in the claims. For example, some of the componentscould be arranged in different locations, and other variations that arelimited only by the scope of the claims.

The invention has been described in the context of preferred and otherembodiments, and not every embodiment of the invention has beendescribed. Obvious modifications and alterations to the describedembodiments are available to those of ordinary skill in the art. Thedisclosed and undisclosed embodiments are not intended to limit orrestrict the scope or applicability of the invention conceived of by theApplicant, but rather, in conformity with the patent laws, Applicantintends to protect fully all such modifications and improvements thatcome within the scope of the following claims.

What is claimed is:
 1. A modularized liquefied natural gas productiontrain, comprising: a framed multi-level structure comprising natural gasliquefaction process systems required for natural gas pretreatment,liquefaction, and refrigerant compression and related hardware includingmechanical and electrical equipment, piping and instrumentation; whereinair coolers are installed on a top level of the structure with otherprocess equipment located on multiple levels underneath the air coolers;wherein the structure has a central pipe rack the runs a longitudinallength of the structure with equipment located on both sides of thecentral pipe rack; and wherein one or more refrigerant compressors andrelated power drivers are located at an end of the structure
 2. Themodularized liquefied natural gas production train of claim 1, whereinthe refrigerant compressors and related power drivers are longitudinallyaligned with the longitudinal axis of the train.
 3. The modularizedliquefied natural gas production train of claim 1, wherein the framedmulti-level structure comprises one single module.
 4. The modularizedliquefied natural gas production train of claim 1, wherein the framedmulti-level structure comprises multiple modules along a longitude ofthe structure direction without impacting a layout of the structure andequipment.
 5. The modularized liquefied natural gas production train ofclaim 1, wherein the multiple modules comprise at least one of a processmodule and a refrigerant compressor module; a pretreatment module, aliquefaction module, and a refrigerant compressor module; and apretreatment module and a liquefaction/refrigerant compressor module. 6.The modularized liquefied natural gas production train of claim 1,wherein the air coolers are installed on a top level of the structureindependent of an existence of one or more cantilever extensionsextending laterally from the multi-level structure.
 7. The modularizedliquefied natural gas production train of claim 6, wherein the aircoolers that are installed on the top level occupy no more than thewidth of the top level.
 8. The modularized liquefied natural gasproduction train of claim 6, wherein tubing coupled with the air coolerscomprise at least portions of high flux tubes.
 9. The modularizedliquefied natural gas production train of claim 1, wherein the aircoolers installed on a top level of the structure are installed so thatair coolers that collectively form a majority heat load of the train andair flow are installed on one portion of the top level to reduce hot airrecirculation and reduce a size of at least a portion of the aircoolers.
 10. The modularized liquefied natural gas production train ofclaim 1, wherein an air cooler located in proximity to a gas turbinecomprises a high air flow fan to reduce hot air recirculation to anintake of the gas turbine.
 11. The modularized liquefied natural gasproduction train of claim 10, further comprising vacant space createdunderneath the central pipe rack is configured to mitigate overpressuredamage in the event of explosion and provide a safe distance betweenequipment and a maintenance space for equipment in a central location.12. The modularized liquefied natural gas production train of claim 1,wherein the one more refrigerant compressors and related power driverslocated at an end of the structure are configured for interchangeablereplacement between a gas turbine driver and an electric motor driver.13. The modularized liquefied natural gas production train of claim 1,wherein a liquefied natural gas liquefier is installed in a module andsupported by structure of the module in proximity to a refrigerantcompressor and configured to reduce hydrocarbon inventory in the trainfor safety.
 14. The modularized liquefied natural gas production trainof claim 13, wherein the liquefier is located at one end of aliquefaction module and a liquefied natural gas rundown line is routedoutside of the liquefaction module boundary from the same end and awayfrom the liquefaction module to reduce presence of the liquefied naturalgas rundown line within the module and inventory of liquefied naturalgas within the module for enhanced safety.
 15. The modularized liquefiednatural gas production train of claim 13, further comprising configuringlocations of the liquefied natural gas liquefier and rundown line andassociated piping to concentrate cryogenic lines and equipment withcryogenic service in an cryogenic area in proximity to an end of themodule.
 16. The modularized and complete liquefied natural gasproduction train of claim 13, wherein at least a portion of theliquefied natural gas rundown line comprises vacuum insulated pipes toat least reduce requirements of liquefied natural gas troughs for spillcontainment.
 17. The modularized liquefied natural gas production trainof claim 1, wherein a plurality of pumps are located on a bottom deck ofthe train along sides of the central corridor for maintenance access.18. The modularized liquefied natural gas production train of claim 17,wherein pumps in the liquefied natural gas liquefier and pre-treatmentportions of the train are located in an area configured for collectionof the potentially contaminated rainfall water underneath the pumps andreduction in capacity requirements of a water treatment system.
 19. Themodularized liquefied natural gas production train of claim 1, whereinat least one large compressor and variable frequency drive is located atan edge of a module of the train for maintenance and safety.
 20. Themodularized liquefied natural gas production train of claim 1, furthercomprising a lift system installed at an end of a module of the trainand configured to move items between an elevation on the train and alower elevation, wherein the central corridor space is configured toallow removal of equipment from within the module and transfer to thehydraulic lift system.
 21. The modularized liquefied natural gasproduction train of claim 20, wherein levels higher than a first levelwith the central corridor are configured with drop zone openings in thelevels to the first level.
 22. The modularized liquefied natural gasproduction train of claim 1, wherein compression equipment is located onone side of the central corridor in a pre-treatment section and processtowers are located on an opposite side of the pipe rack in the centralcorridor.
 23. The modularized liquefied natural gas production train ofclaim 1, wherein a pre-cooling heat exchanger is located on one side ofthe central corridor in a liquefaction section and a liquefier islocated on an opposite side of the central corridor.
 24. The modularizedand complete liquefied natural gas production train of claim 1, furthercomprising local electrical rooms and/or substations located at outsideedges of the train and distal from liquefied natural gas rundown linesand a cryogenic area to have clean air intake access.
 25. Themodularized and complete liquefied natural gas production train of claim1, further comprising local instrument rooms and junction boxes locatedon an outside edge of a module of the train distal from liquefiednatural gas rundown lines and a cryogenic area.
 26. The modularizedcomplete liquefied natural gas production train of claim 1, furthercomprising oily water and amine drain systems pre-installed within atleast one module frame beneath a basement floor distal from liquefiednatural gas rundown lines and a cryogenic area.